The large hose fills 1 pool in 9 hours written as 1/9
The small hose fills 1 pool in 18 hours, written as 1/18
Now you have 1/9 + 1/18 = 1/x ( x is the unknown time for both hoses).
rewrite 1/9 with a common denominator as 1/18:
1/9 = 2/18
Now you have 2/18 + 1/18 = 1/x
Add the left side:
2/18 + 1/18 = 3/18
Now you have 3/18 = 1/x
Cross Multiply:
3x = 18
Divide both sides by 3"
x = 18/3
X = 6
It will take both hoses 6 hours.
Hence the number of packages of screws in each shipping box is: 469
Hence option (B) is correct.
Answer:
4.5 % alloy
Step-by-step explanation:
Let x = amt of 30% alloy
The resulting total is to be 25 oz, therefore:
(25-x) = amt of 5% alloy:
A typical mixture equation:
.30x + .05(25-x) = .20(25)
.30x + 1.25 - .05x = 5 .30x - .05x = 5 - 1.25
.25x = 3.75
x = 3.75%2F.25
x = 15 oz of 30% alloy required
then
25-15 = 10 oz of 5% alloy:
Check solution
.30(15) + .05(10) = .20(25)
4.5 + .5 = 5
Take the absolute value of the difference, then divide it by the original amount
|28 - 24.5| / 28 = 3.5/28 = 0.125..now we multiply that by 100 to get it into a percent 0.125 * 100 = 12.5% <== ur answer
